How Much PSI Should I Put In a 4.80 x 12 Trailer Tire

Updated 06/29/2024 | Published 05/04/2019

Products Featured in This Question

Taskmaster 4.80R12 Radial Trailer Tire - Load Range C

(272)

$104.02

Question:

Hello Trailer I have a 4 x 8 Trailer with the Loadstar 4.80 x 12 DOT K3B5 U12, Nylon 2 Ply. Can you tell me what the PSI should be when hauling less than 100lbs? Many thanks,

asked by: Gary M

Expert Reply:

The psi of your trailer tires will be listed on the side wall. It will list the max psi which is what you will want to fill them to regardless of how much weight you have. For reference, the 4.80 x 12 tires we carry have a 60 psi max for load range B and 90 psi max for load range C. If you would like you can put in less than the maximum psi but this I cannot recommend.

With that being said, while you are looking for the psi range you may want to consider noting the overall condition of the tire as well as how old it is. If you see any cracking on the sidewalls then this is an indication that it will need to be replaced. Also, if the tire is 6 years or older it should be replaced as well. The date code is a four digit number on the sidewall and the last two digits are the year it was made.

If you need a replacement tire we have the Taskmaster 4.80-12 Trailer Tire part # TTWSF48012C for bias ply or the Taskmaster 4.80-12 Trailer Tire part # TT48012C for radial ply. The radials will be better for highway use and they also give you a 81 mph speed rating. They both have a load range c rating which is 990 lbs at 90 psi.

expert reply by: Conner L

Gary

6/23/2024

Have a small trailer 3x5 pulled behind motorcycle. Gear an trailer maby 175-200 lb. 4.80x12" range c speed m. If I run 90psi. Trailer bounced very very bad. I ran 45lbs to reduce bounce, but on 2700 mile trip center wore smooth only leaving tread on outside an inside, as if too much air. Grateful for Suggestions. High pressure bounce Or low pressure replace? Thanks

Kyle S.

6/24/2024

@Gary You can still run your tires at a bit lower psi, but I'm wondering if you have bias tires and not radials? If you have bias tires that would be a part of the reason you are seeing the issue. Bias tires don't flex as much and build up more heat, so they won't wear as even (and will be bouncier). I would 100% go to radials if so, the Taskmaster 4.80R12 # TT48012C.

John J.

6/29/2024

Good afternoon Connor, I have the Haul Master 1090 (Harbor Freight) 40 1/2 × 48 trailer I converted it to a Kayak Trailer and extended the tongue with a 2" × 10 ft square tube going from the back of the trailer to the hitch, I have Sport Trail LH 4.80-12C tires on the trailer. The Kayak is 10 ft--7 inches long and weighs 75 lbs. The tires have 90 PSI, however, when towing wit the kayak or just towing the empty trailer it's making a constant bouncing sound at any speed and the highway roads are smooth. The hitch is stabilized with a uhitch Rattle reducizer. I greased the ball with petroleum jelly. What is causing the constant bouncing (It's a brand new trailer from Harbor Freight) your assistance would greatly be appreciated? Thank you.. John J